提出了海杂波背景下的基于分数阶谱相减的弱运动目标检测方法。该方法通过对回波信号检测单元和参考单元分别作分数阶Fourier变换(FRFT),然后将得到的两个模值相减来构成检测统计量,达到抑制杂波、提高检测概率的目的。利用IPIX实测数据实验表明,所提方法在增加目标与杂波FRFT峰值差、提高信杂比以及检测概率等方面都明显优于仅对回波作FRFT变换。在信杂比降低到-12 dB时仍能很容易地检测出目标。设置适当的恒虚警检测门限,该检测方法能够达到更好的检测效果。
A method based on fractional spectral subtraction for detecting weak targets in sea clutter is proposed. The method applies FRFT(fractional Fourier transform) to detect cell and reference cell respectively. The fractional clutter spectrum is subtracted from the fractional signal-clutter spectrum to enhance the signal and reject the clutter. Experiment using the IPIX data shows that the proposed method has significant advantage in increasing the signal-clutter FRFT peak value difference and enhancing the SCR. When the SCR is reduced to -12 dB, the method can still detect targets easily.